| dc.description.abstract | In this study, synthesis, characterization, and analysis of Fe3O4/SiO2 composite
photocatalyst for degradation through methylene blue (MB) was done. Fe3O4/SiO2
composite prepared using coprecipitation method, started with mixing 3 g Fe3O4 into
40 mL ethanol solution and stirred for t = 1 hour; T = 30℃. Then 1,05 g SiO2 and 4,5
mL NH4OH added and stirred in a fume hood for t = 10 hours; T = 30℃. Aquabides
and ethanol used to obtain neutral pH, then calcination with T = 100℃ until powder
obtained and carried out to characterizing. The test result using Scanning Electron
Microscope (SEM) shown Fe3O4/SiO2 composite has round agglomeration shape with
average particle size 0,17 micrometer, 0,32 micrometer, 0,49 micrometer, 0,46
micrometer, and 0,52 micrometer. There are many gaps that indicated as pores due to
addition of SiO2. X-Ray Diffraction (XRD) testing found Fe3O4 compound identified
as magnetite with cubic crystal and SiO2 as amorphous monoclinic structure. The
addition 1,05 g of SiO2 has 0,84 nm of lattice parameter, 33,57 nm of crystal size, and
49,94% of crystallinity degree. The addition of SiO2 causes crystallite size get smaller.
The test used X-Ray Fluorescence (XRF) shown there are composites with the most
impurity elements like Al, Ti, and Zn can reduce performance. Vibrating Sample
Magnetometer (VSM) testing found the material in this study was soft magnet
characterized by narrow hysterical curve area, with parameters Hc = 184,89 Oe; Ms
= 21,62 emu/g; Mr = 5,32 emu/g. The addition of SiO2 mass will reduced the value
coercivity field. The test result using Ultraviolet - Visible (UV-Vis) found measured
absorbance Methylene Blue occurred at maximum wavelength 664 nm, decreased
average solution concentration up to 2 ppm with 87% absorption efficiency, that
indicated the addition Silica affects selectivity and absorbance in degrading MB dye. | en_US |
